Water-resistant paper and process of making same



Patented at. 3,, 1922'.

WIELMM HOSKINS, T (EHIGAGQ, ILLNOIS.

WATEBPRESISTANT PAPER AND PROCESS GE MAKING SAME.

No Drawing.

in A water resistant or repellant paper may be prepared, in accordance with the present,

invention, by sprinkling or dusting uniformly over the surface of the paper an insoluble soap, such as calcium resinate or oleate, calcium or zinc stearate, or'mixtures of the soaps and removing by brushing or wiping all except the minute proportion which adheres-closely to the surface of the paper and Within its pores. The resultant coatmg 2o upon'the surface of the paper is substantially invisible and appears to be discontinuous in character, being formed of minute adherent particles of the soap. The invention may suitably be carriedout by passing a web of paper througha dust chamber, kept filled with a moving current of dust of the soap employed and then between suitable brushes or doctors to remove the excess soap dust. In general, when both sides of the v paper are treated, the amount of soap required is substantially less than 0.1% of the weight of the paper except in the case of very thin, rough surfaced papers or tissues,

when it may be greater. The treated paper is water resistant and water repellent, al-

though not permanently waterproof, and

may suitably be employed for wrapping purposes, for making drinking cups, etc.

A like discontinuous coating of adherent to soap particles may be applied to paper by assing the paper through a suspension of fine particles of the soap in a. liquid such as water. Thesoap, in powdered form, ifnot already Wet, may befirst wet with a. small at amount of alcohol and. isthen dispersed in water to form a thin suspension. A web of paper may be passed throu h this suspension, excess water drained 3 d the paper Y Application filed March W, 1921. fierial Ido. 451,348.

dried in order to form a coating of the soap or soaps of the character described.

When desired, colored soaps may be employed; for example, soaps of nickel, chromium, copper, etc.

ll claim: I

1. The process of making aperwater resistant which comprises app ying to its surfaces a. coatin of discrete particles of adherent insolubFe soap.

.2. The process of making aperwater resistant which comprises app ying to its surfaces a coatin of discrete particles of adherent insolub e calcium oleate. J

3. The process of making paper water resistant which comprises applying to its surface a coating of adherent insoluble calcium soap, the amount of soap being less than 0.1% of the paper.

4. The'process of making water resistant paper which comprises dusting or sprinkling insoluble soap on the surface of paper and brushing or wiping oil" all except the adherent soap particles.

5. The process of making water resistant paper which comprises dusting or sprinklin calcium stearate on the surface of paper and rushing or wiping ofi' all except the adherent particles of the soap.

6. Water resistant paper consisting of paper having on its surface a discontinuous coating of adherent insoluble soap particles and substantially free from non-adherent particles thereof.

7. Water resistant paper consisting of paper having'on'its surface a discontinuous coating of adherent particles of calcium oleate, and substantially free from non-adherent articles'thereof.

8-. W dter resistant ipaper consisting of paper havin fon its surface a discontinuous coating of a herent particles of calcium oleate, and substantially free from non-adherent particles thereof, the weight of said coating being less than 0.1% of the weight of the paper.

WILLIAM HOSKINS. 

